The present disclosure relates to automatic valves; such as ring valves. Some embodiments of the subject matter disclosed herein relate specifically to reciprocating compressor automatic ring valves. According to a further aspect, the disclosure relates to reciprocating compressors including the automatic ring valves. According to another aspect, the disclosure relates to a shutter for automatic ring valves. According to a further aspect, the disclosure relates to a method for manufacturing a ring shutter for an automatic ring valve.
Automatic valves are commonly used for example in reciprocating compressors. Automatic valves are arranged on both the suction side as well as the discharge side of the compressor, to automatically open and close the suction port and discharge port of the compressor under the control of the pressure inside the compressor cylinder.
As know, an automatic ring valve can comprise a valve guard and a valve seat, the latter provided with circumferentially arranged gas flow passages extending through the valve seat. Also the valve guard is provided with gas flow passages. A plurality of concentrically arranged shutter rings is placed between the valve seat and the valve guard. Each shutter ring is arranged along a set of corresponding annularly arranged gas flow passages of the valve seat. Compression springs are provided between the valve guard and each shutter ring to oppose the movement of the shutter ring from the closed position, wherein the respective set of gas flow passages are closed.
Differential pressure across the valve causes automatic opening and closing of the valve. The crank shaft of reciprocating compressors using such valves can rotate at a rotary speed in the range of for example 100-1200 rpm and typically between 200 and 1000 rpm. The shutter rings are therefore subject to repeated opening and closing strokes at high speed. They are commonly made of composite material, such as short fiber-reinforced synthetic resin to reduce the mass thereof and thus the inertia. The valve seat and the valve guard are typically made of metal.